Compounds containing more than one acrylate or (meth)acrylate group in the molecule have long been known and are used in particular as adhesives and sealing compounds that harden under anaerobic conditions. In many cases, compounds containing at least two (meth)acrylate groups in the molecule are used for these applications. By varying the basic molecule, it is possible to influence certain desired properties of these anaerobic compositions. In addition to a short hardening time, more particularly, a relatively short time before an initial strength is reached, high strengths under thermal load are particularly desirable.
Reaction products of polyfunctional aromatic and aliphatic isocyanates and hydroxyalkyl methacrylates have been known for some time (cf., U.S. Pat. No. 3,425,988). These reaction products may be processed with the usual auxiliary components to form anaerobic sealing compounds and adhesives. They generally show high flexibility and also elasticity. Unfortunately, the strengths obtainable, which are still satisfactory at room temperature or moderately elevated temperatures, are far from satisfactory under relatively intense thermal load.